Birthweight data were classified by the method of reporting in the survey either from an official health card or from mother’s memory. There were substantial differences in the distribution of birthweights by method of reporting. We conclude that the method of recording birthweight can influence birthweight estimates, in particular the proportion of infants classified as low birthweight. This has implications for data collection, the interpretation of survey data and public health policy. The original publication is available at www.springerlink.com The original publication is available at www.springerlink.com